With the development of advanced information society in recent years, the need for larger capacity image information recording is increasing, and a surface recording density as high as 1 Terabit per square inch (Tb/inch2) is required for magnetic recording media. As a magnetic recording medium providing such high recording density, a patterned magnetic recording medium, which isolates magnetic dots using a nonmagnetic material, has been a focus of attention (See Non-patent Reference 1.).
The technique described in Non-patent Reference 1 uses a mask on which resist is patterned by the nanoimprint technology, and isolates magnetic dots by etching a magnetic film using this mask.
It is known that a rapidly quenched Fe—Pt—B alloy ribbon has a double-phase structure consisting of a uniform nanosized amorphous phase and a fcc(γ)-FePt phase, and that structure transforms into a nanostructure exhibiting good hard magnetic property by heat treatment (See Non-patent Reference 2.).    [Non-patent Reference 1] Tsutomu AOYAMA, Isamu SATO, Shunji ISHIO, “Fabrication and magnetic properties of patterned magnetic recording media”, OYO BUTURI, 2003, Vol. 72, No. 3, pp. 298-303    [Non-patent Reference 2] A. Inoue and W. Zhang, J. Appl. Phys., 97, 10H308, 2005